60 research outputs found
EFFECTS OF RELEASE TECHNIQUES ON PARENT-REARED WHOOPING CRANES IN THE EASTERN MIGRATORY POPULATION
Reintroduction of an Eastern Migratory Population (EMP) of whooping cranes (Grus americana) in the United States by release of captive-reared individuals began in 2001. As of 2020, the EMP has approximately 21 breeding pairs and has had limited recruitment of wild-hatched individuals, thus captive-reared juveniles continue to be released into breeding areas in Wisconsin to maintain the population. We investigated the effects of release techniques on survival, behavior, site fidelity, and conspecific associations of 42 captive-parent-reared whooping cranes released during 2013-2019 into the EMP. Individuals were monitored intensively post-release, then as a part of a long-term monitoring program, locational, behavioral, and habitat use data were collected and analyzed. Most cranes roosted in water post-release; however, we documented 4 parent-reared cranes roosting on dry land. Most cranes eventually associated with other whooping cranes; however, juveniles released near single adult cranes were less likely to associate with other whooping cranes during their first migration or winter than juveniles released near other types of whooping crane pairs or groups. Parent-reared and costume-reared whooping cranes had similar rates of survival 1 year post-release (69.0% and 64.4%, respectively). The highest risk of mortality was within the first 100 days post-release, and the leading known causes of death were predation and impact trauma due to powerline or vehicle collisions. Both costume- and parent-reared cranes had strong fidelity to release sites. We advise releasing parent-reared cranes near pairs or groups of whooping cranes and taking measures to reduce the risk of mortality during the immediate period after release (e.g., predator aversion training, marking powerlines)
Mapping the dark matter halo of early-type galaxy NGC 2974 through orbit-based models with combined stellar and cold gas kinematics
We present an orbit-based method of combining stellar and cold gas kinematics to constrain the dark matter profile of early-type galaxies. We apply this method to early-type galaxy NGC 2974, using Pan-STARRS imaging and SAURON stellar kinematics to model the stellar orbits, and introducing H I kinematics from VLA observation as a tracer of the gravitational potential. The introduction of the cold gas kinematics shows a significant effect on the confidence limits of especially the dark halo properties: we exclude more than 95 per cent of models within the 1σ confidence level of Schwarzschild modelling with only stellar kinematics, and reduce the relative uncertainty of the dark matter fraction significantly to 10 per cent within 5Re. Adopting a generalized Navarro-Frenk-White (NFW) dark matter profile, we measure a shallow cuspy inner slope of 0.6^{+0.2}_{-0.3} when including the cold gas kinematics in our model. We cannot constrain the inner slope with the stellar kinematics alone.PostprintPeer reviewe
Anomalous Momentum States, Non-Specular Reflections, and Negative Refraction of Phase-Locked, Second Harmonic Pulses
We simulate and discuss novel spatio-temporal propagation effects that relate
specifically to pulsed, phase-mismatched second harmonic generation in a
negative index material having finite length. Using a generic Drude model for
the dielectric permittivity and magnetic permeability, the fundamental and
second harmonic frequencies are tuned so that the respective indices of
refraction are negative for the pump and positive for the second harmonic
signal. A phase-locking mechanism causes part of the second harmonic signal
generated at the entry surface to become trapped and dragged along by the pump
and to refract negatively, even though the index of refraction at the second
harmonic frequency is positive. These circumstances culminate in the creation
of an anomalous state consisting of a forward-moving second harmonic wave
packet that has negative wave vector and momentum density, which in turn leads
to non-specular reflections at intervening material interfaces. The
forward-generated second harmonic signal trapped under the pump pulse
propagates forward, but has all the attributes of a reflected pulse, similar to
its twin counterpart generated at the surface and freely propagating backward
away from the interface. This describes a new state of negative refraction,
associated with nonlinear frequency conversion and parametric processes,
whereby a beam generated at the interface can refract negatively even though
the index of refraction at that wavelength is positive
Integral-field kinematics and stellar populations of early-type galaxies out to three half-light radii
Funding: STFC grant ST/K502339/1 during the course of this work (NFB), Leverhulme Trust Early Career Fellowship (AW).We observed twelve nearby HI -detected early-type galaxies (ETGs) of stellar mass ∼ 1010 M⊙ ≤ M* ≤1011 M⊙ with the Mitchell Integral-Field Spectrograph, reaching approximately three half-light radii in most cases. We extracted line-of-sight velocity distributions for the stellar and gaseous components. We find little evidence of transitions in the stellar kinematics of the galaxies in our sample beyond the central effective radius, with centrally fast-rotating galaxies remaining fast-rotating and centrally slow-rotating galaxies likewise remaining slow-rotating. This is consistent with these galaxies having not experienced late dry major mergers; however, several of our objects have ionised gas that is misaligned with respect to their stars,suggesting some kind of past interaction. We extract Lick index measurements of the commonly-used Hβ, Fe5015, Mg, b, Fe5270 and Fe5335 absorption features, and we find most galaxies to have flat Hβ gradients and negative Mg, b gradients. We measure gradients of age, metallicity and abundance ratio for our galaxies using spectral fitting, and for the majority of our galaxies find negative age and metallicity gradients. We also find the stellar mass-to-light ratios to decrease with radius for most of the galaxies in our sample. Our results are consistent with a view in which intermediate-mass ETGs experience mostly quiet evolutionary histories, but in which many have experienced some kind of gaseous interaction in recent times.PostprintPeer reviewe
Vegetation Cover Analysis of Hazardous Waste Sites in Utah and Arizona Using Hyperspectral Remote Sensing
This study investigated the usability of hyperspectral remote sensing for characterizing vegetation at hazardous waste sites. The specific objectives of this study were to: (1) estimate leaf-area-index (LAI) of the vegetation using three different methods (i.e., vegetation indices, red-edge positioning (REP), and machine learning regression trees), and (2) map the vegetation cover using machine learning decision trees based on either the scaled reflectance data or mixture tuned matched filtering (MTMF)-derived metrics and vegetation indices. HyMap airborne data (126 bands at 2.3 x 2.3 m spatial resolution), collected over the U. S. Department of Energy uranium processing sites near Monticello, Utah and Monument Valley, Arizona, were used. Grass and shrub species were mixed on an engineered disposal cell cover at the Monticello site while shrub species were dominant in the phytoremediation plantings at the Monument Valley site. Regression trees resulted in the best calibration performance of LAI estimation (R-2 > 0.80. The use of REPs failed to accurately predict LAI (R-2 < 0.2). The use of the MTMF-derived metrics (matched filter scores and infeasibility) and a range of vegetation indices in decision trees improved the vegetation mapping when compared to the decision tree classification using just the scaled reflectance. Results suggest that hyperspectral imagery are useful for characterizing biophysical characteristics (LAI) and vegetation cover on capped hazardous waste sites. However, it is believed that the vegetation mapping would benefit from the use of higher spatial resolution hyperspectral data due to the small size of many of the vegetation patches (<1 m) found on the sites.open111
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Spirit, mind and body: the archaeology of monastic healing
Archaeology and material culture are used in this chapter to consider how monastic experience responded to illness, ageing and disability. The approach taken is influenced by the material study of religion, which interrogates how bodies and things engage to construct the sensory experience of religion, and by practice-based approaches in archaeology, which examine the active role of space and material culture in shaping religious agency and embodiment. The archaeology of monastic healing focuses on the full spectrum of healing technologies, from managing the body in order to prevent illness, through to the treatment of the sick and preparation of the corpse for burial
Cross-oncopanel study reveals high sensitivity and accuracy with overall analytical performance depending on genomic regions
BackgroundTargeted sequencing using oncopanels requires comprehensive assessments of accuracy and detection sensitivity to ensure analytical validity. By employing reference materials characterized by the U.S. Food and Drug Administration-led SEquence Quality Control project phase2 (SEQC2) effort, we perform a cross-platform multi-lab evaluation of eight Pan-Cancer panels to assess best practices for oncopanel sequencing.ResultsAll panels demonstrate high sensitivity across targeted high-confidence coding regions and variant types for the variants previously verified to have variant allele frequency (VAF) in the 5-20% range. Sensitivity is reduced by utilizing VAF thresholds due to inherent variability in VAF measurements. Enforcing a VAF threshold for reporting has a positive impact on reducing false positive calls. Importantly, the false positive rate is found to be significantly higher outside the high-confidence coding regions, resulting in lower reproducibility. Thus, region restriction and VAF thresholds lead to low relative technical variability in estimating promising biomarkers and tumor mutational burden.ConclusionThis comprehensive study provides actionable guidelines for oncopanel sequencing and clear evidence that supports a simplified approach to assess the analytical performance of oncopanels. It will facilitate the rapid implementation, validation, and quality control of oncopanels in clinical use.Peer reviewe
Erratum: Corrigendum: Sequence and comparative analysis of the chicken genome provide unique perspectives on vertebrate evolution
International Chicken Genome Sequencing Consortium.
The Original Article was published on 09 December 2004.
Nature432, 695–716 (2004).
In Table 5 of this Article, the last four values listed in the ‘Copy number’ column were incorrect. These should be: LTR elements, 30,000; DNA transposons, 20,000; simple repeats, 140,000; and satellites, 4,000. These errors do not affect any of the conclusions in our paper.
Additional information.
The online version of the original article can be found at 10.1038/nature0315
Underlying Mechanisms of Gene–Environment Interactions in Externalizing Behavior: A Systematic Review and Search for Theoretical Mechanisms
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